Gyroscopes are used to measure rotation rates or changes in angular velocity about an axis of rotation in many different applications. While a variety of high performance moderately-sized and more affordable gyroscopes for many defense and space applications have been developed, there is a need for still lower cost and/or smaller sized navigation grade gyroscopes for a range of military and commercial applications.
The resonator fiber optic gyroscope (RFOG) can combine strengths of ring laser gyroscopes and interferometric fiber gyroscopes to reach very high sensitivity in a smaller size and lower cost. The RFOG uses lasers to probe the resonances of a ring resonator in clockwise (CW) and counterclockwise (CCW) directions. In implementing a smaller and/or lower cost RFOG, one issue that needs to be addressed is that multiple (up to four) phase locked laser light sources may be needed to provide the light in the gyroscope, which may require a lot of power consumption and undesirably increase production cost. There is also a problem with getting very good bias stability in such a gyroscope.